Method and system for distributing liquid in (meth)acrylic monomer process vessels

Abstract

A method for uniformly distributing a process liquid within a process vessel includes providing a process liquid to a fouling-resistant liquid distributor installed within a process vessel having a cross-sectional area; causing rotational movement of the fouling-resistant liquid distributor; uniformly distributing the process liquid over the cross-sectional area within the process vessel; and simultaneously self-rinsing the fouling-resistant liquid distributor with a portion of the process liquid during uniform distribution. A system is also disclosed which includes a supply of process fluid, a stationary conduit and a liquid distribution head attached to the conduit. The liquid distribution head is motive, powered by a fluid, and includes at least one process liquid delivery port. The at least one process liquid delivery port is configured to provide a +10° or greater angle of liquid coverage when the liquid distribution head is moving.

The invention claimed is: 
     
       1. A method for preventing polymer accumulation at the top of a glacial acrylic acid distillation column, said method comprising:
 a. providing a glacial acrylic acid distillation column, said column comprising, 
 i. a plurality of dual-flow trays, including a top tray, and 
 ii. a vapor space above the top tray of the column, 
 b. providing a fouling-resistant liquid distributor, said distributor comprising a single, spherical distribution head with a plurality of liquid delivery ports, attached to the lower end of a stationary vertical conduit, 
 c. providing GAA Inhibitor Solution, 
 d. positioning said spherical distribution head below the top tangent line of the column, 
 e. supplying said GAA Inhibitor Solution to the upper end of said stationary vertical conduit, thereby causing said distribution head to revolve continuously about the centerline axis of the stationary vertical conduit, 
 wherein said distribution head uniformly distributes GAA Inhibitor Solution over the entire circumference of the top tray of the column, continually wetting all of the interior surfaces within the vapor space above the top tray of the column at a wetting liquid rate of less than 0.5 m3/m2-hr, and simultaneously self-rinsing the exterior surfaces of the stationary vertical conduit and the distribution head. 
 
     
     
       2. The method of  claim 1  wherein the GAA Inhibitor Solution comprises acrylic acid and about 200 ppm MeHQ polymerization inhibitor. 
     
     
       3. The method of  claim 1  wherein the step of continually wetting all of the interior surfaces within the vapor space above the top tray of the column is performed at a wetting liquid rate of 0.05 m3/m2-hr. 
     
     
       4. The method of  claim 1  wherein the single distribution head discharges sufficient liquid GAA Inhibitor Solution to provide uniform coverage over a +300° angle of liquid coverage. 
     
     
       5. A method for preventing polymer accumulation at the top of an acrylic ester distillation column, said method comprising:
 a) providing an acrylic ester distillation column, said column comprising, 
 i. a distillation column head, 
 ii. a plurality of trays, including a top tray, 
 iii. a vapor space above the top tray of the column, and 
 iv. a vessel nozzle located on the distillation column head, 
 b) providing a fouling-resistant liquid distributor, said distributor comprising a fouling resistant liquid spherical distribution head with a plurality of liquid delivery ports, attached to the lower end of a stationary conduit, 
 c) providing a process liquid stream comprising polymerization inhibitor, 
 d) positioning said spherical distribution head below the top tangent line of the column, 
 e) supplying said process liquid stream comprising polymerization inhibitor to the upper end of said stationary conduit, thereby causing said spherical distribution head to revolve continuously about the centerline axis of the conduit, 
 wherein said spherical distribution head uniformly distributes said process liquid stream comprising polymerization inhibitor over the entire circumference of the top tray of the column, continually wetting all of the interior surfaces within the vapor space above the top tray of the column at a wetting liquid rate of less than 0.5 m3/m2-hr, and simultaneously self-rinsing the exterior surfaces of the conduit and the spherical distribution head. 
 
     
     
       6. The method of  claim 5  wherein the step of continually wetting all of the interior surfaces within the vapor space above the top tray of the column is performed at a wetting liquid rate of 0.08 m3/m2-hr. 
     
     
       7. The method of  claim 5  wherein the distribution head discharges sufficient liquid Inhibitor Solution to provide uniform coverage over a +300° angle of liquid coverage. 
     
     
       8. The method of  claim 5  wherein the vessel nozzle is located on the top center of the distillation column head. 
     
     
       9. The method of  claim 5  wherein the fouling resistant liquid distributor further comprises optional conduit ports, and operation of the fouling resistant liquid distributor comprising optional conduit ports also rinses the annular nozzle space formed between the internal surface of the vessel nozzle and the exterior surface of the stationary conduit. 
     
     
       10. The method of  claim 5  wherein the acrylic ester distillation column is a dual-use acrylic ester distillation column that may be employed to produce butyl acrylate or 2-ethylhexylacrylate.